1. Field of the Invention
The present invention relates to the field of the manufacture of glass panels, and in particular to a glass panel stocking system and a stocking method.
2. The Related Arts
Liquid crystal display (LCD) has a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and is thus widely used. Most of the LCDs that are currently available in the market are backlighting LCDs, which comprise an enclosure, a liquid crystal panel arranged in the enclosure, and a backlight module that is arranged in the enclosure. The operation principle of the liquid crystal panel is that liquid crystal molecules are interposed between two parallel glass substrates and the liquid crystal molecules are controlled to rotate by the application of a driving voltage to the two glass substrates in order to refract out light emitting from the backlight module for generating images. Since the liquid crystal panel itself does not emit light, light must be provided by the backlight module in order to normally display images. Thus, the backlight module is one of the key components of an LCD. The backlight module can be classified in two types, namely side-edge backlight module and direct backlight module, according to the position where light gets incident. The direct backlight module comprises a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED), which is arranged at the backside of the liquid crystal panel to form a planar light source that directly provides lighting to the liquid crystal panel. The side-edge backlight module comprises an LED light bar, serving as a backlight source, which is arranged at an edge of a backplane to be located rearward of one side of the liquid crystal panel. The LED light bar emits light that enters a light guide plate (LGP) through a light incident face of the light guide plate and is projected out of a light emergence face of the light guide plate, after being reflected and diffused, to pass through an optic film assembly to form a planar light source for the liquid crystal panel.
In a manufacturing process of the liquid crystal panel, before the glass panels are assembled, they are packaged first, generally packaged in a cassette (CST), and then stacked in a storage zone for subsequent use in a liquid crystal display assembling operation.
Referring to FIGS. 1 and 2, a conventional way of stacking glass panels is carried out with a stocker (STK) system. The stocker system comprises a crane 100, which functions to move a cassette 300 that receives glass panels 302 therein; and a loading and unloading port 500 on which a cassette 300 that contains glass panels 302 therein can be positioned, a mapping bar 520 being provided at the site where the loading and unloading port 500 for inspecting and counting the glass panels 302 received in the cassette 300. A conventional mapping bar 520 generally comprises electro-optical transducers 522 to scan the glass panels 302 contained in the cassette 300 in a top-down layer-by-layer manner in order to carry out inspection and count of the glass panels 302. The operation efficiency is low and further, a mapping bar 520 is required at each loading and unloading port 500, leading to a large number of mapping bars 520 used and thus an increased cost. This is adverse to cost control.